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The use of structure-from-motion, multi-view stereo (SfM-MVS) in the mining industry is well-established for capturing digital data on surface. However, the application of SfM-MVS in active underground mining has received less attention as there are unique challenges that need to be overcome, especially if a procedure is to be applied daily in active mining. Unique challenges include preparation time, camera positioning, illumination and useability. The faces of active development drives are generally only available for a short period before prepared and blasted, thus information is lost if not mapped immediately. Furthermore, due to safety concerns, unsupported faces cannot be approached for physical mapping. SfM-MVS allows these faces to be viewed and mapped in the form of a virtual outcrop, thus, allowing for remote mapping of underground development, which at the Dugald River mine, located in Queensland, Australia, allowed for mapping continuity as staff worked remotely during COVID-19. This contribution describes how to set-up a capture in an underground mine to produce high-quality SfM-MVS 3D reconstructions of development faces. The methodology can be readily incorporated into a standard operating procedure. While the procedure can be used with most photogrammetry software packages that utilise SfM-MVS algorithms, it is best utilised using the provided Python script and Agisoft Metashape Professional v1.6. The script allows for automation of capture processing, which can free up several hours per day compared to user-interacted processing.

The Middle Pennsylvanian Herrin and Springfield coals contain the majority of the Illinois basin’s resources. Many mining issues of these two seams are directly related to the geology of the region, including regional stress, faulting, and facies changes. Some of these conditions are widespread, while others are locally restricted. The long history of mining in these seams has been associated with many difficulties and hard-learned lessons related to mining geology especially concerning aspects of coal quality and roof geology along paleochannels, moisture-sensitivity in shales, fractures and “slips” in shales, floor heave, lateral stresses, clay dikes (veins), and coal balls. Both seams occur within classic “cyclothems,” resulting from sequences of deposition between lowstand and highstand deposition. Transgressive, marine black shales and limestones blanket the coals across much of the basin, except near syndepositional channels where wedges of gray silty shale and interbedded shale and sandstone intervene between the coal and transgressive shale. Differences in the thickness, chemistry and strength of various shales in each sequence influence coal quality and roof conditions in underground mines. Associations of mining geology issues not specifically related to tectonics and horizontal stress, are (1) syndepositional channel and channel margin conditions, (2) post-depositional channels, (3) gray-shale wedge margins, and (4) marine shale roofs; especially where limestones thicken. Many of these features are similar to both seams, while others are more common in the Herrin, than Springfield Coal. Similar conditions occur above other coal beds in the Illinois Basin, as well as coal-bearing strata in other basins. Herein we review horizontal stress, fractures, coal quality, partings, coal balls, clay dikes (veins), dips and swales, floor heave, moisture sensitivity in shales, shale rolls, limestone bosses and cutouts, paleochannels and cutouts, stackrock conditions, paleoslumps, coal riders, kettlebottoms, and concretions in the roof. Hopefully, this summary will be useful for understanding seams with similar geology, but with less research on mining geology or shorter mining histories.

Well-considered schemes that classify ore deposits can be effective contributors to exploration success, understanding of deposit genesis, mining geology, engineering, metallurgy, property valuations and stock market analysis. An effective classification scheme needs to be easy to apply without ambiguity and is much more powerful if based on sound scientific principles. For deposits with economic gold, a useful classification recognises gold-only and gold-plus deposits based upon whether they also have economic base metals. The scheme is easy to apply and in most cases unambiguous for specific deposits and whole provinces. The subdivision has a sound scientific basis that involves the chemistry of gold in relation to metal complexing, salinity of ore-forming fluids and redox state. Forward modelling from chemical principles can be integrated with inverse modelling from observations to add confidence in this classification and thus be used to create exploration opportunities. The Jiaodong gold province of eastern China comprises deposits mostly in granitic rocks with economic gold but low levels of base metals; the inferred ore fluids are of low to moderate salinity. From their gold-only character, several other aspects of their development can be inferred, though the tectonic and metamorphic history remains unresolved. The granitic host rocks appear to reflect a chemically and mechanically favourable site for deposition, not a source for the gold or the ore fluid neither of which have been established yet.

[Extract] Mineral exploration endeavors to find ore deposits (i.e., economically viable concentrations of minerals or metals) for mining purposes. Delineation of targets for mineral exploration is the crucial initial stage in a series of mapping activities that may result in ore deposit discovery. That is because mineral deposits are 'freaks' of nature and, thus, vectoring towards ore deposits based on multi-source and multi-scale geoscience exploration data sets is a multi-faceted spatial problem. Therefore, applications of geocomputation, which is "the art and science of solving complex spatial problems with computers" (Xue et al., 2004), and applications of geological concepts of ore genesis are essential in mineral exploration target delineation.

Surface coal mining technology, practice and development of mining systems are introduced since the founding of China. The development of surface coal mining systems can be classified into two stages: shovel-train mining system used as the major mining technology before 1980, combined mining systems have been used since 1980, that is, shovel-truck mining system used as the major overburden removal system and the shovel truck/crusher/conveyor have been utilized as the major coal winning systems. The characteristics of the second stage in area mining methods include outside waste dumping and then gradually inside dumping in the mined out areas. After analyzing the coal occurrences in China, the practice and application of surface mining technology, it is proposed that the attention should be paid to the problems such as coal haulage system layout design and the reliability improvement of the system of shovel/truck/crusher in the future development of surface coal mining.

Granular activated carbon (GAC) was evaluated as a suitable sorbent for polycyclic aromatic hydrocarbons (PAHs) removal from aqueous solutions. For this purpose, kinetic measurements on the extraction of a family of six PAHs were taken. A morphology study was performed by means of a scanning electron microscopy (SEM) analysis of GAC samples. Analyses of the batch rate data for each PAH were carried out using two kinetic models: the homogenous particle diffusion model (HPDM) and the shell progressive model (SPM). The process was controlled by diffusion rate the solutes (PAHs) that penetrated the reacted layer at PAH concentrations in the range of 0.2–10 mg L−1. The effective particle diffusion coefficients (Deff) derived from the two models were determined from the batch rate data. The Weber and Morris intraparticle diffusion model made a double contribution to the surface and pore diffusivities in the sorption process. The Deff values derived from both the HPMD and SPM equations varied from 1.1×10−13 to 6.0×10−14 m2 s−1. The simplest model, the pore diffusion model, was applied first for data analysis. The model of the next level of complexity, the surface diffusion model, was applied in order to gain a deeper understanding of the diffusion process. This model is able to explain the data, and the apparent surface diffusivities are in the same order of magnitude as the values for the sorption of functionalized aromatic hydrocarbons (phenols and sulphonates)that are described in the literature.

Ore sorting technology has great potential to allow the minerals industry to improve its competitive position through the exploitation of low grade ore reserves and in improved processing operations. The present paper reports on the development of microwave techniques by the CSIRO Division of Minerals to classify iron ore on the basis of predicted metallurgical performance, and the relationship to future ore sorting developments. The use of artificial neural net-based techniques for data analysis and ore classification are described.

The El-Missikat prospect lies in the Eastern Desert of Egypt, 85 km from Qena along the river Nile. The area of the prospect is covered by pink granites of the Gabal (G.) El-Missikat pluton from the south and quartz diorite from the north, as well as wadi alluvium at Wadi El-Missikat, which passes through the study area from south to north. The importance of the study area comes from previous studies, airborne geophysics, surface and mining geology and ground spectrometric and magnetic studies, which prove that the area has radioactive mineralization zones at the northeastern periphery of G. El-Missikat. These mineralized zones he along northeastsouthwest jasperiod veins and shear zones which occur inside the granitic rocks. The previous studies concluded that the radioactive mineralization was mostly associated with sulphides, especially at the reduction zones. These sulphides give a good response to electrical or electromagnetic techniques. Accordingly, the present study uses self potential, electrically induced polarization and horizontal loop electromagnetic surveys to explore the extension of the mineralization zones at the subsurface. The self potential (SP) technique shows that there are numerous (31) mineralized zones. Most of these zones are distributed in the southern part of the area along the contact between the quartz diorite, the granite and the shear zones inside the El-Missikat granitic pluton. In addition, the induced polarization (In method is applied on two selected profiles (450E and 500E) to delineate the subsurface contact between granite and quartz diorite in Wadi El-Missikat and to calculate the shape and depth of the mineralization zones in the subsurface along these profiles. The horizontal loop electromagnetic survey, which was applied on three selected profiles, delineated some weak mineralization occurrences corrosponding to the shear zones. The integration of the results obtained using these three techniques, in addition to the different ground geophysical methods prviously used, make it possible to determine the most appropriate zones for developement of exploration at the area of investigation.

In planning a mine with layered deposits one must decide the ultimate disposition of the material to be mined. Some material will be mined for processing as ore and some will be discarded as waste. Mining equipment can remove the layers of waste and ore separately. There are, however, minimum widths for waste and ore cuts because of the way the equipment is designed and operated. Thus, decisions on the disposition of any given depth interval depend on its ore quality as well as that of neighboring intervals. Information on ore quality by depth is gained by drilling holes into the ore body and measuring the mineral content at periodic intervals. This paper presents a dynamic programming approach that optimizes the cuts for a single drillhole from which the ore qualities are evaluated.We implement a trial version to illustrate the properties of the solution, using Lotus 123.

The types of geological information supplied by trace elements are substantiated by four case-histories in petroleum and mining geology. In the first one, relationships between trace elements, organic matter and depositional environment are emphasized. The second case displays the behaviour of some trace elements resulting from effects of ground water circulation. The third one shows how geological information can be obtained by ascribing concentrations of a given element to its preferential mineralogical bearer. The fourth one is an example of chemical-mineralogical changes in a hydrothermal system.

This paper discusses rock engineering criteria suggested for the design of mine openings on the basis of in-situ stress regime and rock discontinuity conditions. The criteria are based on documented experience for underground civil works in the U.S. and abroad. The relevance of the criteria is demonstrated by reference to selected coal mine examples in Utah and West Virginia. Field instrumentation suitable for the measurement of in-situ stress and for monitoring mine response to stress and rock discontinuity conditions is also discussed from experience at deep, underground coal mines in Colorado, Utah, and West Virginia. Instrumentation for in-situ stress includes the hydraulic fracturing techniques and the overcoring technique; for mine response, instrumentation includes electric, vibrating wire stressmeters in pillars and rock extensometers in mine roofs.